DrFever
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Dolomitic limestone is a type of limestone that includes up to 50 percent dolomite. Normal limestone is primarily made up of calcite and aragonite, but dolomite forms in limestone when the calcium ions in the calcite part of the limestone are replaced by magnesium ions this process is called dolomitization. Dolomitic limestone was once referred to as magnesian limestone in the United States Geological Survey publications, but is now known as dolostone, dolomite rock, dolomite limestone, or dolomitic limestone. Dolomite is a mineral which contains large amounts of calcium and magnesium, which makes it a good fertilizer for nutrient deficient soil.
In addition to working as a fertilizer, dolomitic limestone is also useful for soils that are too acidic, or have an abnormally low pH level. Adding dolostone for the purpose of raising the soils pH level is known as liming. Dolomite stone being sold as liming material typically contains a minimum of 30 percent magnesium.
Dolomite lime fertilizer is certainly allowed in organic gardening. It is not inherently bad, but how it is used in the garden is often detrimental.
The belief is that minerals in your soil are continuously being leached by rain and consequently your soil is always moving towards more acidic.
Dolomite limestone is used to counteract this, to sweeten the soil. It can do that, but that doesnt mean its good.
Minerals may or may not be leaching from your soil. If they are, it could be partially because of rain, but there are other reasons, too.
If your soil is low in organic matter, which is often the case, it probably cant hold onto minerals very well, especially if it is low in clay and high in sand and silt. If you have lots of clay, you probably dont have much to worry about.
Chemical fertilizers cause acidity, so if you use them, that is part of the problem, too.
Whatever the cause, dolomite lime fertilizer is not the answer. Lets look at why garden lime is probably not what you want.
The main point I want to make is that even if minerals are leaching from your soil, it doesnt make sense to blindly go back adding just two of them (the calcium and magnesium in dolomitic lime) without knowing you need them. You might already have too much of one of them. We need to think a little more than that when organic gardening.
Your soil needs a calcium to magnesium ratio of somewhere between 7:1 (sandier soils) and 10:1 (clayier soils). Outside of this range, your soil will often have drainage problems, your plants will often have health problems and insect and disease problems, and you will have weed problems.
One of your most important goals in the garden is to add specific mineral fertilizers to move the calcium to magnesium ratio towards this range.
The problem with dolomite lime? It has a calcium to magnesium ratio of 2:1. Thats way too much magnesium for most soils. Magnesium is certainly an essential mineral. Too much of it, however, causes many problems, compaction being one of the most common, but also pest and weed problems.
You should only use garden lime when you have a soil test showing a huge deficiency of magnesium in your soil.
Even then, calcitic lime (calcium carbonate) is generally the way to go because it has a small amount of magnesium and often a calcium to magnesium ratio of about 6:1, with a calcium content of 30% to 40% or more.
In addition to working as a fertilizer, dolomitic limestone is also useful for soils that are too acidic, or have an abnormally low pH level. Adding dolostone for the purpose of raising the soils pH level is known as liming. Dolomite stone being sold as liming material typically contains a minimum of 30 percent magnesium.
Dolomite lime fertilizer is certainly allowed in organic gardening. It is not inherently bad, but how it is used in the garden is often detrimental.
The belief is that minerals in your soil are continuously being leached by rain and consequently your soil is always moving towards more acidic.
Dolomite limestone is used to counteract this, to sweeten the soil. It can do that, but that doesnt mean its good.
Minerals may or may not be leaching from your soil. If they are, it could be partially because of rain, but there are other reasons, too.
If your soil is low in organic matter, which is often the case, it probably cant hold onto minerals very well, especially if it is low in clay and high in sand and silt. If you have lots of clay, you probably dont have much to worry about.
Chemical fertilizers cause acidity, so if you use them, that is part of the problem, too.
Whatever the cause, dolomite lime fertilizer is not the answer. Lets look at why garden lime is probably not what you want.
The main point I want to make is that even if minerals are leaching from your soil, it doesnt make sense to blindly go back adding just two of them (the calcium and magnesium in dolomitic lime) without knowing you need them. You might already have too much of one of them. We need to think a little more than that when organic gardening.
Your soil needs a calcium to magnesium ratio of somewhere between 7:1 (sandier soils) and 10:1 (clayier soils). Outside of this range, your soil will often have drainage problems, your plants will often have health problems and insect and disease problems, and you will have weed problems.
One of your most important goals in the garden is to add specific mineral fertilizers to move the calcium to magnesium ratio towards this range.
The problem with dolomite lime? It has a calcium to magnesium ratio of 2:1. Thats way too much magnesium for most soils. Magnesium is certainly an essential mineral. Too much of it, however, causes many problems, compaction being one of the most common, but also pest and weed problems.
You should only use garden lime when you have a soil test showing a huge deficiency of magnesium in your soil.
Even then, calcitic lime (calcium carbonate) is generally the way to go because it has a small amount of magnesium and often a calcium to magnesium ratio of about 6:1, with a calcium content of 30% to 40% or more.